#define _CRT_SECURE_NO_WARNINGS 1

#include<string.h>
#include<stdio.h>

//int main()
//{
//	char arr1[] = "abcdxxxxx";
//	char arr2[] = "123454";
//	strncpy(arr1, arr2, 4);
//}

int main()
{
	char arr1[] = "abcdef\0xxxxx";
	char arr2[] = "12345";
	strncat(arr1, arr2, 4);
}